Nokia’s Lumia 900 will land on AT&T in just two days, but could the Finnish phone maker already be working on its next flagship?Phone Arena has received a “non-final poster template” that has allegedly found its way out of Nokia’s offices. Aside from the neon hues — which we love — the most noticeable tidbit here are the words “Windows Phone 8,” which is the next version of Windows Phone that could possibly land later this year. We’re writing this off as a rumor for now, but what do you think about it?